The invention relates to a pump stand for generating and regulating the vacuum intended for a rotary vaporizer, comprising a control device having a control connection to a control unit having at least one control element.
Such vacuum pump stands are required to generate and regulate the vacuum required in rotary evaporators. Here, it is already known to change and readjust the desired processing parameters, for example by changing the rotation of the of the drive engine provided in the pump stand. In such rotary evaporators frequently mixtures of liquids are used having highly volatile components, with their vapors being potentially hazardous. When processing such mixtures of liquids the respective rotary evaporator and the corresponding pump stand must be operated in a fume cupboard, in order to prevent endangering the laboratory personnel. Here, the laboratory personnel must always remain in close proximity in order to observe the functional displays through the divider of the fume cupboard and to monitor the processing parameters, as well as to allow opening the fume cupboard when needed and perhaps activate operating elements provided at the vacuum pump stand, getting exposed to potential health hazards.
This object is attained according to the invention in a pump stand of the type mentioned at the outset, particularly in the control unit being embodied as a remote control unit, being in a wireless control connection to the control device of the pump stand.
From WO 2005/002076 A1 a remote control device is already known, which shall be controllable in a wireless fashion via a remote control unit from a distance and which is designed for the rough handling in the industrial field or in agriculture. In order to allow a secure and definite allocation of a remote control to a device for technical security reasons, and in order to safely avoid any contamination of delicate plug-in contacts even under rough operating conditions it is provided in the device known from WO 2005/002076 A1 that prior to starting operation an allocation mode has to run first, which ensures a definite allocation on the one hand of the device to the corresponding remote control on the other hand. Although the device known from WO 2005/002076 A1 is allegedly provided with a docking station for the remote control, too, at which the remote control can temporarily be fixed, however this fails to change the fact that the above-mentioned device itself can only be controlled by the radio connection, requiring said allocation mode, and not via a wired control connection when the remote control is located in the docking station. The control connection exclusively operating via radio bears the risk, though, that the device must continue operating in an uncontrolled fashion when the batteries are “dead” and that in this situation a controlled connection cannot be reestablished fast enough after the remote control has been returned to the docking station.
From US 2005/0129535 A1 a pump stand with a pump unit is known, which is in a wireless control connection to a control unit. Therefore, the pump unit and the control unit of the above-mentioned pump stand comprise transmitting and receiving devices, allowing an alternating exchange of command and data signals. Here the wireless command and data paths are monitored via a monitoring device, which switches the pump into a safety mode when the command and data paths are interrupted due to malfunction. When this safety mode includes switching the pump to a predetermined pumping operation it bears the risk, though, that this process, among other things also controlled via the pump, requires a pump performance deviating from the one of the predetermined pumping operation in order for example to avoid an overreaction in the process; when in said safety mode the pump known from prior art is set to an off mode, however, any previously achieved processing results may be lost perhaps also depending on the pump.
From EP 1 577 559 A1 a vacuum pump stand is known, in which a vacuum pump is wirelessly control connected to a control unit. In this known vacuum pump stand of prior art, too, the control unit and the pump unit comprise transmitting and receiving devices allowing an alternating exchange of command and data signals. However, here too, there is the risk in this vacuum pump stand of prior art that the pump stand must continue operating in an uncontrolled fashion when the battery in the control unit is “dead” and that in this situation a control connection cannot be reestablished fast enough.
Therefore, the particular object is to provide a pump stand of the type mentioned at the outset, which is characterized in simple handling and largely excludes any risks of health hazards for laboratory personnel.